Sensing Water Absorption in Hygrothermally Aged Epoxies with Terahertz Time-Domain Spectroscopy.

In the field of non-destructive testing, terahertz sensing has been used to analyze a wide range of materials where the most successful applications have involved materials that are semi-transparent to terahertz radiation. In this work, we demonstrate the sensitivity of terahertz time-domain spectroscopy to quantify water absorption in hygrothermally aged simple and commercial epoxy systems supported by conventional gravimetric analysis.